Kilrah/Taranis_120_Mhz

Set the Taranis processor to run at the full 120MHz speed, up from the current 60MHz. This will provide some more power for the advanced features like scripts. 
It comes at a cost of an additional 10mA current draw with the stock battery voltage. 

Not sure it's really needed, but we currently kind of lack the stats to determine it. Would need a breakdown of the time the CPU core is really using for the different tasks with various model setups. Most of the "visible" things are hardware-driven and -constrained, so there is little visible difference. 

The main visible one is the LCD refresh that is noticeably faster (can be seen by moving the stick on the channel monitor page), as that is one thing that is CPU-driven due to the LCD not being connected to a hardware SPI port.